<html lang="en" window-resizable="true" window-width="400dip" window-height="600dip" theme="light">

<head>
    <style src="main.css" />
    <title>Test Grid</title>
</head>

<body>
    <div class="content">
        <div class="row">
            <div class="item red"></div>
            <div class="item green"></div>
            <div class="item yellow"></div>
            <div class="item blue"></div>
        </div>
        <div class="row">
            <div class="item red"></div>
            <div class="item yellow"></div>
            <div class="item blue"></div>
        </div>
    </div>
</body>

</html>